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The Case of the Mysterious Misbehaving Brake Pedal

I have fairly new brakes on my 97 Chevy Tahoe with 202,000+ miles. For the last several months when I come to a stop, sometimes the brakes make a grinding sound (or ‘boy-yoi-yong’ sound- it’s hard to tell) and the brake pedal feels like it ‘slips’ although the brakes do always stop the car. The brake don’t always do this but it happens at least once or twice a day. Sometimes the problems is very mild, other times it’s very noticeable. have it checked by two mechanics and they can’t get the brakes to misbehave so they can’t find the problem. All they did was flush the brake fluid twice and tell me it MIGHT be the master cylinder or the ABS system. My husband got laid off from his job and I am disabled. We can’t afford to start fixing everything the mechanics THINK might be wrong with the brakes. Any ideas- I am desperate! Thanks.

I am assuming the mechanics took off your rims and visually inspected and measured the pads and rotors?
Perhaps the brake pads you used are simply noisier than the ones you had before.
Did you get the rotors machined during that last brake job?
While it’s not always necessary, it does tend to reduce the kind of complaints you have.

If this has rear drum brakes, I’d have the brake hardware (springs, etc.) checked out. I’d also look at the parking brake assembly and make sure all is working right.

If you do have ABS, I would say that you have found what is causing the sound and the slipping feeling. Are the stops wet or icy when this happens? If so, there may be nothing to worry about because the symptoms are normal when ABS is needed to prevent skidding. Dirt on the road will cause the ABS to operate.

Your ABS may be malfunctioning. That won’t be fixed without some money being thrown around. Remove the ABS fuse and if the symptoms quit there could be an ABS problem. If you get brake lockup which will cause a skid, there may be other brake problems which will be easier to diagnose because you will know which wheel skidded. Maybe that will help with the money problem.

Sometimes brake rotors will hint at what’s wrong. The worst looking one may be saying “look closer at my area”. If it looks like the Galactica and the Cylons fought a battle on it; I would call that suspicious indeed.